"It might have been our best ballgame in all three phases," Harbaugh said. "You're never as good as you think. I know that there were some mistakes that we made."
Harbaugh watched Brandon Peters throw two touchdown passes and Chris Evans run for two scores as Michigan had a 28-0 lead before the second quarter was halfway over thanks to Peters' passing and some madcap miscues by Maryland.
Harbaugh even joked about an exchange he had with kicker Quinn Nordin, who missed a 31-yard field goal late in the first half.
"Start making them. You've got to make them," Harbaugh told his kicker. "I think anger's a powerful motivator," he said with a laugh.
Peters threw touchdown passes of 33 yards to Zach Gentry and 3 yards to Sean McKeon. Henry Poggi and Evans ran for scores. Evans, who scored from a yard out in the second quarter, added a 17-yard run late in the fourth quarter.
"It felt like there were a couple of things we needed to clean up out there," Gentry said. "Overall, I felt like we were flying around and we did a great job of executing everything."
The Terrapins started their fourth quarterback of the season, Ryan Brand, but unlike the previous three, he couldn't come close to engineering a win. Brand was 16 for 35 for 136 yards.
"I thought, for the most part, there were some drives that we could have — and should have — finished," Maryland coach DJ Durkin said.
In one particularly embarrassing sequence, Lorenzo Harrison badly overthrew Brand with lots of running room ahead of the quarterback, and three plays later, caught a pass from Brand and managed to lose 14 yards.
Brand said that the big deficit didn't we faze him.
"You try not to think about the scoreboard too much because then you start to force things and make bad decisions," Brand said. "Obviously, I know the situation that we're in, but I try not to put too much thought into it."
Trailing 14-0, Maryland tried a fake punt from its own 30. After Jaquille Veii gained just 3 yards and turned the ball over to Michigan, the Wolverines immediately scored on the 33-yard pass from Peters to Gentry.
After a 29-yard pass to Taivon Jacobs was overturned by replay, Michigan blocked Wade Lees' punt. Two plays later, Peters hit McKeon for a 3-yard pass, and the Wolverines' lead was 28-0 with 8:21 to play in the first half.
In the second half, Maryland scored on a 20-yard field goal by Henry Darmstadter and a 10-yard pass from Brand to Jacobs.
Michigan: This lopsided victory should thrust Michigan into the Top 20 and provide added momentum for their final two games against Wisconsin and Ohio State. The Wolverines haven't had much luck against the top teams in the Big Ten, but they still have more than enough talent to beat the lesser teams in the conference.
Maryland: This loss means that the Terrapins would have to win their final two games — both against ranked teams, Michigan State and Penn State — to be guaranteed a bowl appearance and a chance at their first winning season since 2014.
WOLVERINES OUTGAINED: Despite Harbaugh's ebullience, Michigan was outgained by Maryland 340-305. "The execution was so good the whole game and then we made a few mistakes defensively and make a few mistakes offensively," Harbaugh said.
JOHNSON SETS MARK: Maryland RB Ty Johnson ran for 71 yards and became the 13th Terrapin to rush for more than 2,000 yards in his career.
QUOTABLE: "I heard it's pretty rowdy there," Peters on Michigan traveling to play No. 6 Wisconsin on Nov. 18.
Michigan: The Wolverines hope to make a statement on road against the No. 6 Badgers, who are still unbeaten after beating Iowa 38-14.
Maryland: The Terrapins wrap up their road schedule at Michigan State, ranked 13th before Saturday's 48-3 loss to Ohio State.